OK - So I'm looking for a nice SLR set up - This is what I have been looking at. I have used an SLR quite a bit - do some HDR stuff - alot of just amatuer stuff - nothing but a hobby - but I want the best bang for my buck.

Of your list, I like the Pentax K20D. I use Nikon for most of my picture taking. But I think Pentax has the best bang for the buck right now. The only exception to this is if you think in the near future you really want to work towards being a pro shooter. Even then Pentax would still be a good camera. Just Nikon or Canon would give more options for specality lenses.

Now having said that. The Nikon D5000 does not have a body mounted AF drive. Which means it will only AF the new lenses. This may not be a draw back if you want to buy all new equipment anyway. But the fact is some of their older lenses are very good. You can still use the older ones just no AF.

Olympus I have never used or know much about. So, I can't say yes or no to them.

The K20D though. The more I read, the more I think its the best bang for the buck. And although Nikon and Canon have more current New lens choices. The Pentax can be used professionally with a good photographer behind it. They do have good lenses, the major 3rd party lens makers make lenses for it. Pentax has body based vibration control so lenses can be made less expensive, and every lens will have the benefits of it. Their bodies are weather sealed. And like Nikon, Pentax can use their old lenses AF and MF. Canon and Nikon are in the lead but I wouldn't discount Pentax too much.

I currently have 4 Nikon DSLR's and 1 Canon DSLR. And am considering getting a Pentax to play around with. I am just a camera nut.

The reason not being their gear is 'better' than any of the other brands, that's bull of course. They simply have a much better selections for lenses and other accessories (including those offered by other companies e.g. Simga, Tokina, et. al).

Also your chances of finding a replacement rechargeable battery in five years from now, for Canon or Nikon would be much better than it would for Pentax, Sony or Olympus.

You don't mention Canon in your list, so that leaves Nikon.

If you're limited to $1000 though, why wouldn't you consider the D40 rather than the D5000, and be left with more $ for lenses?

I've personally considered the D40 and the only reason I did not end up buying it was that I have some AF-D lenses (no internal AF motor), which would not AF on the D40, so I ended up with a D70 at the time, which still faithfully serves me.